Prediction of Central Post-Stroke Pain by Quantitative Sensory Testing

Abstract

Objective: Among patients with acute stroke, we aimed to identify those who will later develop central post-stroke pain (CPSP) versus those who will not (non-pain sensory stroke [NPSS]) by assessing potential differences in somatosensory profile patterns and evaluating their potential as predictors of CPSP.

Methods: In a prospective longitudinal study on 75 acute stroke patients with somatosensory symptoms, we performed quantitative somatosensory testing (QST) in the acute/subacute phase (within 10 days) and on follow-up visits for 12 months. Based on previous QST studies, we hypothesized that QST values of cold detection threshold (CDT) and dynamic mechanical allodynia (DMA) would differ between CPSP and NPSS patients before the onset of pain. Mann-Whitney U-tests and mixed analysis of variances with Bonferroni corrections were performed to compare z-normalized QST scores between both groups.

Results: In total, 26 patients (34.7%) developed CPSP. In the acute phase, CPSP patients showed contralesional cold hypoesthesia compared to NPSS patients (p = 0.04), but no DMA differences. Additional exploratory analysis showed NPSS patients exhibit cold hyperalgesia on the contralesional side compared to the ipsilesional side, not seen in CPSP patients (p = 0.011). A gradient-boosting approach to predicting CPSP from QST patterns before pain onset had an overall accuracy of 84.6%, with a recall and precision of 75%. Notably, both in the acute and the chronic phase, approximately 80% of CPSP and NPSS patients showed bilateral QST abnormalities.

Interpretation: Cold perception differences between CPSP and NPSS patients appear early post stroke before pain onset. Prediction of CPSP through QST patterns seems feasible. ANN NEUROL 2025;97:507-520.

FIGURE 1

Pain localization. Pain localization of patients with central post stroke pain (CPSP) (n = 26). All unilateral right‐sided infarcts with clinical symptoms have been flipped to the left side so that all symptoms are depicted on the same body side. Pain contralesional to the stroke lesion manifested in the face (n = 4), perioral region (n = 8), shoulder and upper arm (n = 10), forearm (n = 12), hand (n = 21), chest and abdomen (n = 3), buttock (n = 5), thigh (n = 4), lower leg (n = 7) and foot (n = 8). [Color figure can be viewed at www.annalsofneurology.org]

FIGURE 2

Prediction of pain occurrence from the acute setting QST parameters. QST on the contralesional side is indicated with “_c” (eg, _cCDT). Side‐to‐side differences between the ipsilesional and the contralesional side are indicated with “_sd” (eg, _sdCDT). Gradient boosting classification (with leave‐one out cross validation) based on QST findings in acute stage to predict pain occurrence. (A) ROC curve of the gradient boosting classifier. (B) Confusion matrix. (C) Odds ratio plot of the logistic regression. (D) Feature importance showing the contribution of the 6 QST features included in the classifier model. CDT, cold detection threshold; CPSP, central post‐stroke pain; CPT, cold pain threshold; HPT, heat pain threshold; NIHSS, National Institutes of Health Stroke scale; PPT, pressure pain threshold; QST, quantitative sensory testing. [Color figure can be viewed at www.annalsofneurology.org]